In modern days, people are increasingly fond of recording their life by taking photos. Thus, photography has drawn an increasing amount of attention, whether the photos are taken as an occupation or as an interest. People often encounter two kinds of problems when they take photos with a camera. On one hand, in order to highlight characteristics or achieve a special effect, people usually bring a target object in focus while blurring its surrounding background. On the other hand, when photographing themes such as a scenery, a flower or a building, people always hope to exhibit all elements in the entire picture, i.e., to obtain a photo with all depth of field. This requires each point of the shot to be accurately focused. However, for an ordinary camera, once the photographing process is over, the focus can no longer be changed in the post-processing of a photo, which restricts flexibility in post-processing the photo.
A light field camera is usually adopted for taking photos so as to deal with the above two kinds of problems. Alternatively, photos of a same scene can be taken manually with different focuses and then combined into a photo with all depth of field by means of image processing software.
However, an imaging portion of a light field camera is generally composed of a microlens array and an image sensor array. Such a lens array is usually composed of thousands of microlenses. With such a light field camera, a light field of incident light beams can be recorded. After that, images are decoded through complicated physical and mathematical computation by using software, and thereby processed into final images. The microlens array of the light field camera is formed by arranging conventional microlenses. However, the conventional lenses cannot implement a rapid and flexible zooming function. Therefore, the technical solution, which acquires images with different focuses by means of a light field camera, cannot be achieved without complicated physical and mathematical knowledge. These complicated techniques are not favorable for the market popularization of a light field camera. Correspondingly, the method, which combines manual photography with image processing software to create a photo with all depth of field, involves a complex procedure and requires high photography techniques of a photographer. Specifically, the photographer may need to manually control the uniformity of an exposure level, ensure an optimal aperture or even resort to things like a tripod to ensure stability of the camera.